-- mom tonight on this Mother's Day a moment on the Little League field that carried an important medical -- for assault and eight year old player hit with the ball his heart suddenly stopping. But what that -- from the other teen did next saved his life. Here tonight ABC's do you but he didn't. A miracle happened on this Little League field it was just another Saturday afternoon for mom Maureen -- -- watching her son played ball in New Jersey. When suddenly a ball hit another little boy Ian agree feet as he slid into third base. He stood -- and then his whole body just collapse -- the -- I just ran just trying to save them. Maureen remembers her CPR training from twenty years ago. It is more concussions and back I think his fourth time I think they turn into the compression as -- -- -- -- -- the puff of -- -- he can't. And he starts dating I think terminal there. Here's what he was breathing platforms are being a good night there was -- mom and I didn't feel a little boy you -- -- back I'm. Cardiac arrest on the field is rare but it's happened before just last month in San Diego -- sixteen year old died when a soft ball hit his chest. When it comes to the heart over the -- area. It can transmit -- energy. And that can create an electrical signal that can disturb the heart. Point electrical signal and start a cascade of events that lead to the heart stopped today Maureen urges every to take a simple CPR course. Because it saved a little boy's life. -- this morning breaking up knowing that he's going to be fine and just you know that his mother -- my mother's and that's all that matters to me. Such a special woman and tonight little -- is still in the hospital with doctors walking over him. But they tell us he is doing well his mother is so grateful to --

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